tpad = {}
tpad.version = "1.2"
tpad.mod_name = minetest.get_current_modname()
tpad.texture = "tpad-texture.png"
tpad.mesh = "tpad-mesh.obj"
tpad.nodename = "tpad:tpad"
tpad.mod_path = minetest.get_modpath(tpad.mod_name)

local PRIVATE_PAD_STRING = "Private (only owner)"
local  PUBLIC_PAD_STRING = "Public (only owner's network)"
local  GLOBAL_PAD_STRING = "Global (any network)"

local PRIVATE_PAD = 1
local  PUBLIC_PAD = 2
local  GLOBAL_PAD = 4

local RED_ESCAPE = minetest.get_color_escape_sequence("#FF0000")
local GREEN_ESCAPE = minetest.get_color_escape_sequence("#00FF00")
local BLUE_ESCAPE = minetest.get_color_escape_sequence("#0000FF")
local YELLOW_ESCAPE = minetest.get_color_escape_sequence("#FFFF00")
local CYAN_ESCAPE = minetest.get_color_escape_sequence("#00FFFF")
local MAGENTA_ESCAPE = minetest.get_color_escape_sequence("#FF00FF")
local WHITE_ESCAPE = minetest.get_color_escape_sequence("#FFFFFF")

local OWNER_ESCAPE_COLOR = CYAN_ESCAPE

local padtype_flag_to_string = {
   [PRIVATE_PAD] = PRIVATE_PAD_STRING,
    [PUBLIC_PAD] =  PUBLIC_PAD_STRING,
    [GLOBAL_PAD] =  GLOBAL_PAD_STRING,
}

local padtype_string_to_flag = {
   [PRIVATE_PAD_STRING] = PRIVATE_PAD,
    [PUBLIC_PAD_STRING] =  PUBLIC_PAD,
    [GLOBAL_PAD_STRING] =  GLOBAL_PAD,
}

local short_padtype_string = {
   [PRIVATE_PAD] = "private",
    [PUBLIC_PAD] = "public",
    [GLOBAL_PAD] = "global",
}

local smartfs = dofile(tpad.mod_path .. "/lib/smartfs.lua")
local notify = dofile(tpad.mod_path .. "/notify.lua")

-- workaround storage to tell the main dialog about the last clicked pad
local last_clicked_pos = {}

-- workaround storage to tell the main dialog about last selected pad in the lists
local last_selected_index = {}
local last_selected_global_index = {}

-- memory of shown waypoints
local waypoint_hud_ids = {}

minetest.register_privilege("tpad_admin", {
   description = "Can edit and destroy any tpad",
   give_to_singleplayer = true,
})

-- ========================================================================
-- local helpers
-- ========================================================================

local function copy_file(source, dest)
   local src_file = io.open(source, "rb")
   if not src_file then
      return false, "copy_file() unable to open source for reading"
   end
   local src_data = src_file:read("*all")
   src_file:close()

   local dest_file = io.open(dest, "wb")
   if not dest_file then
      return false, "copy_file() unable to open dest for writing"
   end
   dest_file:write(src_data)
   dest_file:close()
   return true, "files copied successfully"
end

-- alias to make copy_file() available to storage.lua
tpad._copy_file = copy_file

local function custom_or_default(modname, path, filename)
   local default_filename = "default/" .. filename
   local full_filename = path .. "/custom." .. filename
   local full_default_filename = path .. "/" .. default_filename

   os.rename(path .. "/" .. filename, full_filename)

   local file = io.open(full_filename, "rb")
   if not file then
      minetest.debug("[" .. modname .. "] Copying " .. default_filename .. " to " .. filename .. " (path: " .. path .. ")")
      local success, err = copy_file(full_default_filename, full_filename)
      if not success then
         minetest.debug("[" .. modname .. "] " .. err)
         return false
      end
      file = io.open(full_filename, "rb")
      if not file then
         minetest.debug("[" .. modname .. "] Unable to load " .. filename .. " file from path " .. path)
         return false
      end
   end
   file:close()
   return full_filename
end

-- load storage facilities and verify it
dofile(tpad.mod_path .. "/storage.lua")

-- ========================================================================
-- load custom recipe
-- ========================================================================

local recipes_filename = custom_or_default(tpad.mod_name, tpad.mod_path, "recipes.lua")
if recipes_filename then
   local recipes = dofile(recipes_filename)
   if type(recipes) == "table" and recipes[tpad.nodename] then
      minetest.register_craft({
         output = tpad.nodename,
         recipe = recipes[tpad.nodename],
      })
   end
end

-- ========================================================================
-- callback bound in register_chatcommand("tpad")
-- ========================================================================

function tpad.command(playername, param)
   tpad.hud_off(playername)
   if(param == "off") then return end

   local player = minetest.get_player_by_name(playername)
   local pads = tpad._get_stored_pads(playername)
   local shortest_distance = nil
   local closest_pad = nil
   local playerpos = player:getpos()
   for strpos, pad in pairs(pads) do
      local pos = minetest.string_to_pos(strpos)
      local distance = vector.distance(pos, playerpos)
      if not shortest_distance or distance < shortest_distance then
         closest_pad = {
            pos = pos,
            name = pad.name .. " " .. strpos,
         }
         shortest_distance = distance
      end
   end
   if closest_pad then
      waypoint_hud_ids[playername] = player:hud_add({
         hud_elem_type = "waypoint",
         name = closest_pad.name,
         world_pos = closest_pad.pos,
         number = 0xFF0000,
      })
      notify(playername, "Waypoint to " .. closest_pad.name .. " displayed")
   end
end

function tpad.hud_off(playername)
   local player = minetest.get_player_by_name(playername)
   local hud_id = waypoint_hud_ids[playername]
   if hud_id then
      player:hud_remove(hud_id)
   end
end

-- ========================================================================
-- callbacks bound in register_node()
-- ========================================================================

function tpad.get_pos_from_pointed(pointed)
   local node_above = minetest.get_node_or_nil(pointed.above)
   local node_under = minetest.get_node_or_nil(pointed.under)

   if not node_above or not node_under then return end

   local def_above = minetest.registered_nodes[node_above.name]
                  or minetest.nodedef_default
   local def_under = minetest.registered_nodes[node_under.name]
                  or minetest.nodedef_default

   if not def_above.buildable_to and not def_under.buildable_to then return end

   if def_under.buildable_to then
      return pointed.under
   end

   return pointed.above
end

function tpad.on_place(itemstack, placer, pointed_thing)
   if tpad.max_total_pads_reached(placer) then
      notify.warn(placer, "You can't place any more pads")
      return itemstack
   end
   local pos = tpad.get_pos_from_pointed(pointed_thing) or {}
   itemstack = minetest.rotate_node(itemstack, placer, pointed_thing)
   local placed = minetest.get_node_or_nil(pos)
   if placed and placed.name == tpad.nodename then
      local meta = minetest.get_meta(pos)
      local playername = placer:get_player_name()
      meta:set_string("owner", playername)
      meta:set_string("infotext", "TPAD Station by " .. playername .. " - right click to interact")
      tpad.set_pad_data(pos, "", PRIVATE_PAD_STRING)
   end
   return itemstack
end

local submit = {}

function tpad.max_total_pads_reached(placer)
   local placername = placer:get_player_name()
   if minetest.get_player_privs(placername).tpad_admin then
      return false
   end
   local localnet = submit.local_helper(placername)
   return #localnet.by_index >= tpad.get_max_total_pads()
end

function tpad.max_global_pads_reached(playername)
   if minetest.get_player_privs(playername).tpad_admin then
      return false
   end
   local localnet = submit.local_helper(playername)
   local count = 0
   for _, pad in pairs(localnet.by_name) do
      if pad.type == GLOBAL_PAD then
         count = count + 1
      end
   end
   return count >= tpad.get_max_global_pads()
end

function submit.global_helper()
   local allpads = tpad._get_all_pads()
   local result = {
      by_name = {},
      by_index = {},
   }
   for ownername, pads in pairs(allpads) do
      for strpos, pad in pairs(pads) do
         if pad.type == GLOBAL_PAD then
            pad = tpad.decorate_pad_data(strpos, pad, ownername)
            table.insert(result.by_index, pad.global_fullname)
            result.by_name[pad.global_fullname] = pad
         end
      end
   end
   table.sort(result.by_index)
   return result
end

function submit.local_helper(ownername, omit_private_pads)
   local pads = tpad._get_stored_pads(ownername)
   local result = {
      by_name = {},
      by_index = {},
   }
   for strpos, pad in pairs(pads) do
      local skip = omit_private_pads and pad.type == PRIVATE_PAD
      if not skip then
         pad = tpad.decorate_pad_data(strpos, pad, ownername)
         table.insert(result.by_index, pad.local_fullname)
         result.by_name[pad.local_fullname] = pad
      end
   end
   table.sort(result.by_index)
   return result
end

function submit.save(form)
   if form.playername ~= form.ownername and not minetest.get_player_privs(form.playername).tpad_admin then
      notify.warn(form.playername, "The selected pad doesn't belong to you")
      return
   end
   local padname = form.state:get("padname_field"):getText()
   local strpadtype = form.state:get("padtype_dropdown"):getSelectedItem()
   if strpadtype == GLOBAL_PAD_STRING and tpad.max_global_pads_reached(form.playername) then
      notify.warn(form.playername, "Can't add more pads to the Global Network, set to 'Public' instead")
      strpadtype = PUBLIC_PAD_STRING
   end
   tpad.set_pad_data(form.clicked_pos, padname, strpadtype)
end

function submit.teleport(form)
   local pads_listbox = form.state:get("pads_listbox")
   local selected_item = pads_listbox:getSelectedItem()
   local pad
   if form.globalnet then
      pad = form.globalnet.by_name[selected_item]
   else
      pad = form.localnet.by_name[selected_item]
   end
   if not pad then
      notify.err(form.playername, "Error! Missing pad data!")
      return
   end
   local player = minetest.get_player_by_name(form.playername)
   player:move_to(pad.pos, false)

   local padname = form.globalnet and pad.global_fullname or pad.local_fullname
   notify(form.playername, "Teleported to " .. padname)

   tpad.hud_off(form.playername)
   minetest.after(0, function()
      minetest.close_formspec(form.playername, form.formname)
   end)
end

function submit.admin(form)
   form.state = tpad.forms.admin:show(form.playername)
   form.formname = "tpad.forms.admin"

   local max_total_field = form.state:get("max_total_field")
   max_total_field:setText(tpad.get_max_total_pads())

   local max_global_field = form.state:get("max_global_field")
   max_global_field:setText(tpad.get_max_global_pads())

   local function admin_save()
      local max_total = tonumber(max_total_field:getText())
      local max_global = tonumber(max_global_field:getText())
      tpad.set_max_total_pads(max_total)
      tpad.set_max_global_pads(max_global)
      minetest.after(0, function()
         minetest.close_formspec(form.playername, form.formname)
      end)
   end
   max_total_field:onKeyEnter(admin_save)
   max_total_field:onKeyEnter(admin_save)
   form.state:get("save_button"):onClick(admin_save)
end

function submit.global(form)
   if minetest.get_player_privs(form.playername).tpad_admin then
      form.state = tpad.forms.global_network_admin:show(form.playername)
      form.formname = "tpad.forms.global_network_admin"
      form.state:get("admin_button"):onClick(function()
         minetest.after(0, function()
            submit.admin(form)
         end)
      end)
   else
      form.state = tpad.forms.global_network:show(form.playername)
      form.formname = "tpad.forms.global_network"
   end

   form.globalnet = submit.global_helper()

   local last_index = last_selected_global_index[form.playername]
   local pads_listbox = form.state:get("pads_listbox")

   pads_listbox:clearItems()
   for _, pad_item in ipairs(form.globalnet.by_index) do
      pads_listbox:addItem(pad_item)
   end

   pads_listbox:setSelected(last_index)
   pads_listbox:onClick(function()
      last_selected_global_index[form.playername] = pads_listbox:getSelected()
   end)

   pads_listbox:onDoubleClick(function() submit.teleport(form) end)
   form.state:get("teleport_button"):onClick(function() submit.teleport(form) end)

   form.state:get("local_button"):onClick(function()
      minetest.after(0, function()
         tpad.on_rightclick(form.clicked_pos, form.node, form.clicker)
      end)
   end)
end

function submit.delete(form)
   minetest.after(0, function()
      local pads_listbox = form.state:get("pads_listbox")
      local selected_item = pads_listbox:getSelectedItem()
      local delete_pad = form.localnet.by_name[selected_item]

      if not delete_pad then
         notify.warn(form.playername, "Please select a pad first")
         return
      end

      if form.playername ~= form.ownername and not minetest.get_player_privs(form.playername).tpad_admin then
         notify.warn(form.playername, "The selected pad doesn't belong to you")
         return
      end

      if minetest.pos_to_string(delete_pad.pos) == minetest.pos_to_string(form.clicked_pos) then
         notify.warn(form.playername, "You can't delete the current pad, destroy it manually")
         return
      end

      local function reshow_main()
         minetest.after(0, function()
            tpad.on_rightclick(form.clicked_pos, form.node, minetest.get_player_by_name(form.playername))
         end)
      end

      local delete_state = tpad.forms.confirm_pad_deletion:show(form.playername)
      delete_state:get("padname_label"):setText(
         YELLOW_ESCAPE .. delete_pad.local_fullname ..
         WHITE_ESCAPE .. " by " ..
         OWNER_ESCAPE_COLOR .. form.ownername
      )

      local confirm_button = delete_state:get("confirm_button")
      confirm_button:onClick(function()
         last_selected_index[form.playername .. ":" .. form.ownername] = nil
         tpad.del_pad(form.ownername, delete_pad.pos)
         minetest.remove_node(delete_pad.pos)
         notify(form.playername, "Pad " .. delete_pad.local_fullname .. " destroyed")
         reshow_main()
      end)

      local deny_button = delete_state:get("deny_button")
      deny_button:onClick(reshow_main)
   end)
end

function tpad.on_rightclick(clicked_pos, node, clicker)
   local playername = clicker:get_player_name()
   local clicked_meta = minetest.get_meta(clicked_pos)
   local ownername = clicked_meta:get_string("owner")
   local pad = tpad.get_pad_data(clicked_pos)

   if not pad or not ownername then
      notify.err(playername, "Error! Missing pad data!")
      return
   end

   local form = {}

   form.playername = playername
   form.clicker = clicker
   form.ownername = ownername
   form.clicked_pos = clicked_pos
   form.node = node
   form.omit_private_pads = false

   last_clicked_pos[playername] = clicked_pos;
   if ownername == playername or minetest.get_player_privs(playername).tpad_admin then
      form.formname = "tpad.forms.main_owner"
      form.state = tpad.forms.main_owner:show(playername)
      local padname_field = form.state:get("padname_field")
      padname_field:setLabel("This pad name (owned by " .. OWNER_ESCAPE_COLOR .. ownername .. WHITE_ESCAPE .. ")")
      padname_field:setText(pad.name)
      padname_field:onKeyEnter(function() submit.save(form) end)
      form.state:get("save_button"):onClick(function() submit.save(form) end)
      form.state:get("delete_button"):onClick(function() submit.delete(form) end)
      form.state:get("padtype_dropdown"):setSelectedItem(padtype_flag_to_string[pad.type])
   elseif pad.type == PRIVATE_PAD then
      notify.warn(playername, "This pad is private")
      return
   else
      form.omit_private_pads = true
      form.formname = "tpad.forms.main_visitor"
      form.state = tpad.forms.main_visitor:show(playername)
      form.state:get("visitor_label"):setText("Pad \"" .. pad.name .. "\", owned by " .. OWNER_ESCAPE_COLOR .. ownername)
   end

   form.localnet = submit.local_helper(ownername, form.omit_private_pads)

   local last_click_key = playername .. ":" .. ownername
   local last_index = last_selected_index[last_click_key]

   local pads_listbox = form.state:get("pads_listbox")
   pads_listbox:clearItems()
   for _, pad_item in ipairs(form.localnet.by_index) do
      pads_listbox:addItem(pad_item)
   end
   pads_listbox:setSelected(last_index)
   pads_listbox:onClick(function()
      last_selected_index[last_click_key] = pads_listbox:getSelected()
   end)

   pads_listbox:onDoubleClick(function() submit.teleport(form) end)
   form.state:get("teleport_button"):onClick(function() submit.teleport(form) end)
   form.state:get("global_button"):onClick(function()
      minetest.after(0, function()
         submit.global(form)
      end)
   end)

end

function tpad.can_dig(pos, player)
   local meta = minetest.get_meta(pos)
   local ownername = meta:get_string("owner")
   local playername = player:get_player_name()
   if ownername == "" or ownername == nil or playername == ownername
         or minetest.get_player_privs(playername).tpad_admin then
      return true
   end
   notify.warn(playername, "This pad doesn't belong to you")
   return false
end

function tpad.on_destruct(pos)
   local meta = minetest.get_meta(pos)
   local ownername = meta:get_string("owner")
   tpad.del_pad(ownername, pos)
end

-- ========================================================================
-- forms
-- ========================================================================

tpad.forms = {}

local function forms_add_padlist(state, is_global)
   local pads_listbox = state:listbox(0.2, 2.4, 7.6, 4, "pads_listbox", {})
   local teleport_button = state:button(0.2, 7, 1.5, 0, "teleport_button", "Teleport")
   local close_button = state:button(6.5, 7, 1.5, 0, "close_button", "Close")
   close_button:setClose(true)
   if is_global then
      local local_button = state:button(1.8, 7, 2.5, 0, "local_button", "Local Network")
      local_button:setClose(true)
   else
      local global_button = state:button(1.8, 7, 2.5, 0, "global_button", "Global Network")
      global_button:setClose(true)
   end
   state:label(0.2, 7.5, "teleport_label", "(you can doubleclick on a pad to teleport)")
end

tpad.forms.main_owner = smartfs.create("tpad.forms.main_owner", function(state)
   state:size(8, 8);
   state:field(0.5, 1, 6, 0, "padname_field", "", "")
   local save_button = state:button(6.5, 0.7, 1.5, 0, "save_button", "Save")
   save_button:setClose(true)

   local padtype_dropdown = state:dropdown(0.2, 1.2, 6.4, 0, "padtype_dropdown")
   padtype_dropdown:addItem(PRIVATE_PAD_STRING)
   padtype_dropdown:addItem(PUBLIC_PAD_STRING)
   padtype_dropdown:addItem(GLOBAL_PAD_STRING)

   local delete_button = state:button(4.4, 7, 1.5, 0, "delete_button", "Delete")

   forms_add_padlist(state)
end)

tpad.forms.main_visitor = smartfs.create("tpad.forms.main_visitor", function(state)
   state:size(8, 8)
   state:label(0.2, 1, "visitor_label", "")
   forms_add_padlist(state)
end)

tpad.forms.confirm_pad_deletion = smartfs.create("tpad.forms.confirm_pad_deletion", function(state)
   state:size(8, 2.5)
   state:label(0, 0, "intro_label", "Are you sure you want to destroy pad")
   state:label(0, 0.5, "padname_label", "")
   state:label(0, 1, "outro_label", "(you will not get the pad back)")
   state:button(0, 2.2, 2, 0, "confirm_button", "Yes, delete it")
   state:button(6, 2.2, 2, 0, "deny_button", "No, keep it")
end)

tpad.forms.global_network = smartfs.create("tpad.forms.global_network", function(state)
   state:size(8, 8)
   state:label(0.2, 1, "visitor_label", "Pick a pad from the Global Pads Network")
   local is_global = true
   forms_add_padlist(state, is_global)
end)

tpad.forms.global_network_admin = smartfs.create("tpad.forms.global_network_admin", function(state)
   state:size(8, 8)
   state:label(0.2, 1, "visitor_label", "Pick a pad from the Global Pads Network")
   local admin_button = state:button(4.4, 7, 1.5, 0, "admin_button", "Admin")
   admin_button:setClose(true)
   local is_global = true
   forms_add_padlist(state, is_global)
end)

tpad.forms.admin = smartfs.create("tpad.forms.admin", function(state)
   state:size(8, 8)
   state:label(0.2, 0.2, "admin_label", "TPAD Settings")
   state:field(0.5, 2, 6, 0, "max_total_field", "Max total pads per player")
   state:field(0.5, 3.5, 6, 0, "max_global_field", "Max global pads per player")
   local save_button = state:button(6.5, 0.7, 1.5, 0, "save_button", "Save")
   save_button:setClose(true)
   local close_button = state:button(6.5, 7, 1.5, 0, "close_button", "Close")
   close_button:setClose(true)
end)

-- ========================================================================
-- helper functions
-- ========================================================================

function tpad.decorate_pad_data(pos, pad, ownername)
   pad = table.copy(pad)
   if type(pos) == "string" then
      pad.strpos = pos
      pad.pos = minetest.string_to_pos(pos)
   else
      pad.pos = pos
      pad.strpos = minetest.pos_to_string(pos)
   end
   pad.owner = ownername
   pad.name = pad.name or ""
   pad.type = pad.type or PUBLIC_PAD
   pad.local_fullname = pad.name .. " " .. pad.strpos .. " " .. short_padtype_string[pad.type]
   pad.global_fullname = "[" .. ownername .. "] " .. pad.name .. " " .. pad.strpos
   return pad
end

function tpad.get_pad_data(pos)
   local meta = minetest.get_meta(pos)
   local ownername = meta:get_string("owner")
   local pads = tpad._get_stored_pads(ownername)
   local strpos = minetest.pos_to_string(pos)
   local pad = pads[strpos]
   if not pad then return end
   return tpad.decorate_pad_data(pos, pad, ownername)
end

function tpad.set_pad_data(pos, padname, padtype)
   local meta = minetest.get_meta(pos)
   local ownername = meta:get_string("owner")
   local pads = tpad._get_stored_pads(ownername)
   local strpos = minetest.pos_to_string(pos)
   local pad = pads[strpos]
   if not pad then
      pad = {}
   end
   pad.name = padname
   pad.type = padtype_string_to_flag[padtype]
   pads[strpos] = pad
   tpad._set_stored_pads(ownername, pads)
end

function tpad.del_pad(ownername, pos)
   local pads = tpad._get_stored_pads(ownername)
   pads[minetest.pos_to_string(pos)] = nil
   tpad._set_stored_pads(ownername, pads)
end

-- ========================================================================
-- register node and bind callbacks
-- ========================================================================

local collision_box =  {
   type = "fixed",
   fixed = {
      { -0.5,   -0.5,  -0.5,   0.5,  -0.3, 0.5 },
   }
}

minetest.register_node(tpad.nodename, {
   drawtype = "mesh",
   tiles = { tpad.texture },
   mesh = tpad.mesh,
   paramtype = "light",
   paramtype2 = "facedir",
   on_place = tpad.on_place,
   collision_box = collision_box,
   selection_box = collision_box,
   description = "Teleporter Pad",
   groups = {choppy = 2, dig_immediate = 2},
   on_rightclick = tpad.on_rightclick,
   can_dig = tpad.can_dig,
   on_destruct = tpad.on_destruct,
})

minetest.register_chatcommand("tpad", {func = tpad.command})
